Syringe



United States Patent() 3,279,654 SYRINGE Richard L.` Pierick, 2800 Tiffin, Des lMoines, Iowa Filed Feb. 8, 1965, Ser. No. 431,128 12 Claims. (Cl. 222-137) This invention relates to a syringe, and more particularly to a syringe wherein one part of the charge to be injected thereby is initially contained in one element of .the syringe and another part of the charge is initially contained in another, separate element of the syringe. The elements of the syringe are manipulable to accomplish admixture of the components into the one charge, and then are operable as a piston and cylinder means to expel the resulting charge lin the hypodermic administration thereof.

As is well known, many compounds, mixtures, or solutions deteriorate with time or under varying conditions of temperature, light or other changing surroundings. The attempted mixing of such compounds, mixtures, or solutions at the point of use can be extremely diicult if not impossible relative to accurate measurement and sanitary requirements.

Attempts have been made, nevertheless, to solve these problems by compartmentizing the ingredients and components in a single syringe unit, with the compartments separated 'by a wall, diaphragm, or the like which is broken or pierced immediately prior to use of the syringe. These structures, whereas providing an advance in this field, have not been completely satisfactory.

It is an object, therefore, of this invention to provide an improved syringe of multi-compartment type.

It is another object of this invention to provide a two part syringe wherein one part contains one component of a charge the other part contains another component of the charge, and the parts are manipulable together to eect an admixture, then to effect an injection of same.

Yet another object .of this invention is to provide a simple, two part syringe of plastic or the likeV which obviates the need for rubber or like members or membranes useable therewith, which obviates in fact the presence of any material foreign to the plastic or like basic material, and which obviates the need for piercing, breaking or in any way displacing a wall or the like.

Still another object of this invention is to provide a syringe of a two part, tw-o compartment, telescopically arranged structure, wherein absolutely perfect sanitation is provided, no contamination of one component of a charge with another component being possible.

It is an other object of this invention to provide a two part, two compartment type syringe where the arrangement is such that upon one part telescopically entering the other part, air within .the rst part is discharged rearwardly past the axially forwardly moving second part, thus eecting an easier relative axial movement together off the two parts.

It is still another object of this invention to provide a syringe of a Itwo compartment, two part type carrying at least a pair of components of a charge, which is manipulable to effect a mixing immediately prior to use of the components, said mixing being accomplished entirely by gravity.

. Yet another object of this invention is the provision of a syringe employing only a casing for containing one component of a chargeto be injected by the syringe,v and a plunger slida'fble into the casing, and with the plunger containing another component of the charge, and wherein the casing and the plunger are operable in one position to effect a transportation condition with the components sealed olf, operable in another position to provide a mixing condition where the coponents are mixed together by gravity within the casing, and where the components are 3,279,654 Patented Oct. 18, 1966 ICC operable in a third position to have the casing assuming the function of a cylinder with the plunger assuming the function of a piston to eject .the mixed charge from the casing.

It is an other object of this invention t-o provide a syringe which is economical to manufacture, simple and rugged of construction, and effective in use, and further wherein after use, the syringe can be reused with the proper sanitary precautions being taken.V

These objects and other features and advantages of this invention will be readily apparent according to the following description when taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is an exploded, sectional view of the elements of this invention taken along the longitudinal axis of the syringe;

FIG. 2 is a longitudinal, sectional view of the syringe, showing the parts thereof in a transportation position, with a pair of components -to make up an injection charge shown in separated compartments;

FIG. 3 is an enlarged, fragmentary detail View of a certain area of FIG. 2;

FIG. 4 is a fragmentary, sectional View similar to FIG. 2, and wherein the plunger part of the syringe is shown in a second position permitting thereby the components to be mixed;

FIG. 5 is an enlarged, fragmentary detail view of a certain area of FIG. 4;

FIG. y6 is a view similar to FIG. 2, and showing the parts in a third position to permit the escape of air from the casing part rearwardly past the plunger;

fFIG 7 is a fragmentary detail view of a certain area of FIG. 6; and

FIG. 8 is a view similar to FIG. 2, wherein the syringe has been rotated -to a position immediately prior to use, with the plunger in a fourth position and with a hypodermic needle unit attached to the exposed end of the casing.

Referring now to the drawings, a preferred embodiment of the syringe of this invention is indicated generally at 10 in FIGS. 1 and =2. The syringe 10 comprises basically a casing r11 ha-ving an open rear end 12, and the nozzletype front end 13 of which is normally closed by a cap 14.v A plunger 16 is pro-vided for axial, reciprocable insertion into the casing :111, having a closed front end 17 and an.

. open rear end '18 normally closed by a langed knob 19.

Y cylindrical Ibody 2-1 the inner wall surface 22 of which has a substantially constant diameter. An annular end -llange 23 is provided at the rear end of the casing body 21, and .the internal peripheral edge 24 of which is beveled to aid the insertion thjerein of the plunger 16.

A blister 'L6 1s formed within the Iwall 22 by an enlarged waist portion intermediate the front and rear ends 13 and 12, respectively, of the casing. The blister 26 has an an. nular shape, and the internal radius or diameter of which is greater than the internal diameter of the wall 22. The length of the blister 26, -which length extends parallel to the longitudinal axis of the casing body 21, is of a pre-A determined length, and with the blister 26 being spaced adjacent to and intermediate a rear body portion 27 and a front body portion 28 of the body 21.

With the cap 14 (FIG. -2) closing the front end 1-3 of the casing 11, prior to shipment thereof a component `29 of a charge to be injected by the syringe 10 is placed within the body 21. Although this component can be either a liquid or a solid, it is shown herein as a solid.

More particularly as to the plunger 16, it comprises also 'a cylindrical body 31, the outer diameter of which is and 33 effecting a seal with the interior'surface of the` `wall 22 at any time either one or both engage the Wall 22.

The vseals 32 and 33 are spaced longitudinally apart a length the distance of which is less .than the length of the iblister 26. This is clearly illustrated by referring to FIG. 7 where it is seen that the length of the blister 26,4 as

measured between a pair of shoulders 38 and 39 formed vthe plunger body 31 between the seals 32 and 33.

The plunger 16 is completed by a quartet of arcuately and equallyY spaced apertures (only three showing) 34, 35, and 36. Prior to shipment, with the knob y19 removed and with the plunger 16 inserted into the casing 11 in the position shown in FIGS. 2 and 3, the other component 37 of the charge to be injected by the syringe 10 is placed within the plunger body 31. This component is shown as a liquid.

The position of the syringe in FIG. 2 is its transportation position. The two components 29 and 37 are separated, one inthe casing 11 and the ot-herin the plunger 16, by the sealed nature of the seals 32 and 33, `particularly the front seal 33 (FIG. 3), with the wall 22` surface of -the casing body 21. Furthermore, although the component 37 is movable within the plunger body 31, it can not escape therefrom through the aperatures 34-36 except as to be contained between the seals 32 and 33, due to the sealing nature of lthese two seals.

The frictional engagement of both seals 32 and 33 with the casing body 21 suciently is tight such that ordinary transportation jarring of the syringe 10 in the FIG. 2 condition would not cause relative movement of the casing 11 and 'the plunger k16. Further, the shipping container itself could be molded to tit the parts of lthe syringe in their FIG. 2 positions to aid in preventing relative movement.

At the point of use the syringe 10 is grasped in the normal manner -with the fingers below the ange 23 of the casing 11, and =with the thumb against the plunger knob 19. The plunger 16 is thenmoved into the casing 11,ei'fecting actually a relative movementy of both parts.

When the plunger 16 is moved axially into the casing 111so that the front seal 33 has moved past the rear shoulder 38 (FIGS. 4 and 5), thus transversely aligning the plunger apertures 34-36 with the blister 26,' theair trapped within the plunger 16 and also within the casing -11 is equalized, and then the medicant component 37 within the plunger is free to How by gravity downwardly into the casing body 21. This How is indicated by the arrows in FIGS. 4-and 5. Continued axial movement of the plunger 16 into the casing 11 brings the parts to their third relative position best illustrated in FIGS.- 6 and 7.

It is well known that -air is present in the casing body 21, along with the charge component 29 contained therein, in the position of the parts of `FIG. 2. Also, the cap 14 for the casing body 21 can not @be removed until the charge components are completely mixed. Thus, as the plunger :16 continues to move as a piston into the casing 11, which now functions as a cylinder for the piston, a.

lin the body 21, is greater .than the longitudinal length of ciency of the hypodermic needle insertion and ejection of the charge. u

In the present embodiment, howeventhe structure 1s so arranged to provide suiiicient relief of the air pressure. to obviate any problems caused thereby. Referring to` FIGS. 6 and 7, with both seals 32 and 33 of the plunger` 16 positioned .within the blister 26 and between `the shoulders 38 and 39, rendering the seals ineffective thereby,

any air pressure built up within the plunger body 31 and and within the cylinder body 21 is relieved thereby. The

relief is indicated by the arrows in FIGS. 6 and 7, wherein,

due to the reduced outer diameter of the plunger` body 31, relative to inner diameter of the casing wall 22, an annular space 4|1 (FIG. 7) is formed therebetween. As

the space 41 is open to the rear end 12 of the casing 11,1

the air under pressure is free .to escape.

It will be observed here that the exterior of the plunger -body 31 could -be somewhat varied from the` present showing without impairing the function or the effectiveness ofy the syringe 10. For example, rather than having a Apair of seals 32 and 33, one annular seal having the same outer diameter and the same longitudinal length ofthe two seals could be used. Furthermore, the remainder'of the body 31 could have the same outer diameter as the one annular seal, but with one or more longitudinally extended grooves formed in the body to provide for the escape of air.

thereby.` Additionally, the inner diameter of the casing front lbody por-tion 28 could be slightly greater than the inner diameter of the rear body portion 27 to aid the inward movement of the plunger 16.

Continued movement of the plunger 16 into the casing l1 brings the front seal 33 again into sealing engagement with the casing wall 22 (FIG.` 8), the blister 26 V'having been passed. The combined components 29` and 37 now` sealed within the remaining casing chamber can now be throughly shakenif this be necessary. The syringe -10 is then turned upside down, or turned to `a position from that of FIGS. l-7,`whereby the change rests against the front end 17 of the plunger 16 (FIG. 8) by gravity.'

In this position of the syringe 10, the cap `14 can be removed and a hypodermic needle Aunit 42 substituted therefor. The syringe 10is now ready for use. The plunger 16 is then inserted further into the casing .11 to effect an egress of the ycharge contained therein through the needle unit 42.

Athough a preferred embodiment of this invention has been described and disclosed hereinbefore, itis to be remembered that various modifications and alternate arrangements may be made without departing from the true spirit and scope of the invention as Vdefined in the appended claims.

I claim:

1. A syringe comprising in combination:

an elongated casing having an open rear end,and adapted to contain within the interior thereof one component of a charge to be injected by the syringe, said casing interior having at least a portion thereof with a substantially constant internal diameter;

a blister formed inv said casing by a portion of said casing having a radius greater than the normal radius of said constant diameter interior, said 4blister having a certain length parallel to the longitudinal axis of said casing; and

an elongated plunger insertable into said casing rear end, said plunger closed at a front end, releasably sealed at the rear end, and havin-g a cavity formed therein adapted to contain a second componentv of of said casing interior, whereby said plunger is tightly slidable within said casing, said seals having a certain length therebetween less than the length of said blister;

said plunger having further an opening in communication with said cavity formed therein between said seals, said casing interior and said plunger cavity fluidly communicable upon transverse alignment of said opening with said blister, whereby said second component is moveable by gravity into said casing interior for mixing with said one component.

2. A syringe comprising in combination:

an elongated casing having an open rear end and having a cylindrical interior formed by a cylindrical wall, said casing adapted to contain one component of a change to be injected by the syringe, said casing interior having at least -a portion thereof with a substantially constant internal diameter;

a blister formed in said wall by a portion of said wall having a radius greater than the radius of the said constant diameter remainder of said interior, said blister having a certain length parallel to the longitudinal axis of said casing; and

an elongated plunger insertable into said casing rear end, said plunger closed at a fr-ont end, releasably sealed at a rear end, and having a cavity formed therein adapted to contain a second component of the charge to be ejected by the syringe;

said plunger exterior having a diameter less than said casing constant internal diameter and having -a pair of longitudinally spaced seals formed on the exterior thereof, the outer diameter of said seals being identical, being greater than the outer diameter of the remainder of said plunger exterior, and being substantially equal to said constant internal diameter of said casing interior, whereby said plunger is tightly slidable within said casing, said seals having a certain length therebetween less than' the length of s-aid blister;

said plunger having further an opening in communication with said cavity formed therein between said seals, said casing interior and said plunger cavity iluidly communicable upon transverse `alignment of said opening with said blister, whereby said second component is movable by gravity into said 'casing interior for mixing with said one component.

3. A syringe comprising in combination:

an elongated casing having an open rear end, and adapted to contain within the interior thereof one component of a charge to be injected by theV syringe, said casing interior having at least a portion thereof a substantally constant internal diameter;

a blister formed in said casing by a portion of said casting having a radius greater than normal radius of said constant diameter interior, said Vblister having a certain length parallel to the longitudinal axis of said casing; and

an enlongated, cylinderical plunger insertable into said casing rear end and axially reciprocable therein, said plunger closed at a front end and having a knob removably inserted into an c-pen rear end thereof, said plunger having further a cavity formed therein adapted to contain a second component of the charge to be ejected by the syringe;

said plunger exterior having a diameter less than said casing constant internal diameter and having a pair of longitudinally spaced seals formed on the exterior thereof, the outer diameter of said seals being identical, being greater than the outer diameter of the remainder of said plunger exterior, and being substantially equal to said constant internal diameter of said casing interior, whereby said plunger is tightly slidable within said casing, said seals having a certain length therebetween less than the length of said blister;

said plunger having further an opening in communication with said cavity formed therein between said seals, said casing interior and said plunger cavity fluidly communicable upon transverse alignment of said opening with said blister, whereby said second component is movable by gravity into said casing interior for mixing with said one component.

4. A syringe `comprising in combination:

an elongated casing having an open rear end, and adapted to contain within the interior thereof one component of a. charge to be injected by the syringe, lsaid casing interior having Vat least a portion thereof a constant internal diameter;

an annular blister formed in said casing by a waist portion thereof having a radius greater than the radius of the constant diameter remainder of said casing interior, said blister having a certain length parallel to the longitudinal axis of said casing; and

an elongated plunger insertable into said casing rear end, said plunger closed at a front end, releasably sealed at a lrear end, and having a cavity formed therein adapted to contain a second component of the charge to be ejected by the syringe;

said plunger exterior having a diameter less than said casing constant internal diameter and having a pair of longitudinally spaced seals formed on the exterior thereof, the outer diameter of said seals being identical, being greater than the outer diameter of the remainder of said plunger exterior, and being substantially equal to said constant internal diameter of said casing interior, whereby said plunger is tightly slidable within said casing, said seals having a certain length therebetween less than the length of said blister;

said plunger having further an opening in communication with said cavity formed therein between said seals, said casing interior and said plunger cavity fluidly communicable upon transverse alignment of said opening with said blister, whereby said second component is movable by gravity into said casing interior for mixing with said one component.

5. A syringe comprising in combination:

an elongated casing having an open rear end, and adapted to contain within the interior thereof one component of a charge to be injected by the syringe, said casing interior having at least a portion thereof a constant internal diameter;

a blister formed in said casing by a portion of said casing having a radius greater than the normal radius of said constant diameter interior, said blister having a certain length parallel to the longitudinal axis of said casing; and

an elongated ,plunger insertable into said casing rear end, said plunger closed at a front end, releasably sealed at a rear end, and having -a cavity formed therein adapted to contain a second component of the charge to be ejected by the syringe;

said plunger exterior having a substantially constant diameter, having a pair of longitudinally spaced, annular seals formed on the exterior surface thereof, the diameter of said seals being identical, being greater than the diameter of the remainder of the exterior surface of said plunger, and being substantially equal to said casing constant internal diameter, whereby said plunger is frictionally slidable within said casing, said seals having .a length therebetween longitudinally of said plunger less than the length of said blister;

said plunger having furt'her an opening in communication with said cavity formed therein between said seals, said casing interior and said plunger cavity fluidly communicable upon transverse alignment of said opening with said blister, whereby said second component is movable by gravity into said casing interior for mixing `with said one component.

6. A syringe comprising in combination:

yan elongated casing having an open rear end, and adapted to contain within the interior thereof one component of a charge to be injected by the syringe, said casing interior having at least a portion thereof a constant internal diameter;

a blister formed in said casing by a yportion of said casing having a radius greater than the normal radius of said constant diameter interior, said blister having a certain length parallel to the longitudinal axis of said casing; and

an elongated plunger insertable intosaidcasing rear end, said plunger closed at a front end, releasably sealed at a rear end, and lhaving a cavity formed therein adapted to contain a second component of the charge to be ejected by the syringe;

said plunger exterior having a diameter less than said casing constant internal diameter and having a pair of longitudinally spaced seals formed on the exterior thereof, the outer diameter of said seals being identic'al, being greater than the outer diameter of the remainder of said plunger exterior, and beingl substantially equal to said constant internal diameter of said casing interior, whereby said plunger is tightly slida'ble within said casing, said seals having a certain length therebetween less than the length of said blister;

said plunger having further a plurality of larcuately spaced openings in communication with said cavity formed therein between said seals, said casing interior and said plunger cavity iluidly communicable upon transverse alignment of said openings with said blister, whereby said second component is movable by gravity into said casing interior for mixing with Said one component.

7. A syringe comprising in combination:

an elongated casing having an open rear end, and adapted to contain within the interior thereof one component of a charge to be injected by the syringe, said casing interior having at least a portion thereof a constant internal diameter;

an annular blister formed in said casing by a waist portion thereof having a radius greater than the radius of the constant diameter remainder of said casing interior, said blister having a certain length parallel to the longitudinal axis of said casing; andan elongated plunger insertable into said casing rear end, said plunger closed at a front end, releasably sealed at a rear end, and having a cavity formed therein adapted to contain a second component of the charge to be ejected by the syringe;

said plunger exterior having a substantially constant diameter, having a pair of longitudinally spaced, annular seals formed on the exterior surface thereof, the diameter of said seals being identical, being greater than the diameter of the remainder of the exterior surface of said plunger, and being substantially equal to said casing constant internal diameter, whereby said plunger is frictionally slidable within said casing, said seals having a length therebetween longitudinally of said plunger less than the length of said blister;

`said plunger having further an opening in communication with said cavity formed therein between said seals, said casing interior and said plunger `cavity uidly communicable upon transverse alignment of said opening with said blister, whereby said second component is movable by gravity into said casing interior for mixing with said one component.

8. A syringe comprising in combinationz.

an elongated ycasing having tan open rear end, and adapted to contain within the interior thereof one component of a charge to be injected by the syringe, said casing interior having yat least a portion thereof a constant internal diameter;

an annular blister formed in said casing by a waist portion thereof having a radius greater than -the radius of the constant diameter remainder of said casing interior, said blister having a certain length parallel to the longitudinal axis of said casing; and

an elongated plunger insertable into said casing rear end, said plunger `closed at a front end, releasably sealed at a rear end, and having a cavity `formed therein adapted to contain a second component of the charge to be ejected by the springe;

said plunger exterior having a substantially const-ant diameter, having a pair of longitudinally spaced, an-

nular seals formed on the exterior surface thereof,` the diameter of said seals being identical, being greater than the diameter of the remainder of the exterior surface of said plunger, and being substantially equal to said casing constant internal diameter, where. by said plunger is frictionally slidable Within said casing, said seals having a length therebetween loni gitudinally of said plunger` less than the length of said blister;

said plunger having further a plurality of`arcu-ately spaced openings in communication with said cavity formed therein between said seals, said casing intei rior and said plunger cavity uidly communicable upon transverse alignment of said openings with said blister, whereby said second com-ponent is movable by gravity into said casing interior for mixing with said one component.

9. A syringe comprising in combination:

an elongated casing having an open rear end, and adapted to contain within the interior thereof one cornponent of a charge to be injected by the syringe, said casing interior having at least a portion thereof a constant internal diameter;

a blister formed in said casing by a portion of said casing having a radius greater than the normal radius of said constant diameter interior, said blister having a certain length parallel to the longitudinal axis of said casing; and

an elongated plunger insertable into said casing rear said seals having a length therebetween longitudinal-` ly of said plunger less than the length of said blister;`

said plunger having further an opening in communicatioin with said cavity formed therein between said seals, said casing interior and said plunger cavity fluidly communicable upon transverse alignment of said opening with said blister, whereby said second component is movable by gravity into said casing interior for mixing with said one component.

10. A syringe comprising in combination:

an elongated casing having an open rear end, and adapted to contain within the interior thereof one component'of a charge to be injected by the syringe, said casing interior having at least a portionthereof -a constant internal diameter;

interior, said blister having a certain length parallel to the longitudinal axis of said casing; and

an elongated plunger insertable into said casing rear` end, said plunger closed at a front end, 'releasably` sealed vat a rea-r end, and having a cavity formed therein adapted to contain a second component of the charge to be ejected by the syringe;

said plunger exterior having a substantially constant diameter, having a pair of longitudinally spaced, annular seals formed on the exterior surface thereof, the diameter of said seals being identical, being greater than the diameter of the remainder of the exterior surface of said plunger, and being substantially equal to said casing constant internal diameter, whereby said plunger is tightly slidable within said casing, said seals having a length therebetween longitudinally of said plunger less than the length of said blister;

said plunger having further an opening in communication with said cavity formed therein between said seals, said casing interior and said plunger cavity lluidly communicable upon transverse alignment of said `opening with said blister, whereby said second component is movable by gravity into said casing interior for mixing with said one component.

11. A syringe comprising in combination:

an elongated casing having an open rear end, and adapted to contain within the interior thereof one cornponent of a charge to be injected by the syringe, said casing interi-or having at least a portion thereof a constant internal diameter;

an -annular blister formed in said casing by a waist portion thereof having a radius greater than the radius of the constant diameter remainder of said casing interior, said blister having a certain length parallel to the longitudinal axis of said casing; vand an elongated plunger insertable into said casing rear end, said plunger closed at a front end, releasably sealed at a rear end, and having a cavity formed therein adapted to contain .a second component of the charge to be ejected by the syringe;

said plunger exterior having ya substantially constant diameter, having a pair of longitudinally spaced, annular seals formed on the exterior surface thereof, the diameter of said seals being identical, bei-ng greater than the diameter of the remainder of the exterior surface of said plunger, and being substantially equal to said casing constant internal diameter, whereby said plunger is tightly slidable Within said casing, said seals having Ia length therebetween longitudinally of said plunger less than the length of said blister;

said plunger having further a plurality of arcuately spaced openings in communication with said cavity formed therein between said seals, said -casing interior and said plunger cavity fluidly communicable upon -transverse alignment of said openings with said blister, whereby said second component is movable by gravity into said casing interior for mixing with said one component.

12. A syringe comprising in combination:

an elongated casing having an open rear end, and adapted to contain within the interior thereof one component of .a charge to be injected by the syringe7 said casing interior having at least a portion thereof a constant internal diameter;

Ia blister formed in said casing by a portion of said casing having a radius greater than the normal radius of said constant diameter interior, said blister having a certain length parallel to the longitudinal axis of said casing; and

an elongated plunger insertable into said casing rear end, said plunger closed at a front end, releasably sealed at a rear end, and having a cavity formed therein adapted to contain a second component of the charge to be ejected by the syringe;

said plunger exterior having an annular seal portion adjacent said front end, with the remainder of the exterior of said plunger having at least one relief groove formed therein extended from the seal portion to the rear end thereof, the outer diameter of said seal portion being substantially equal to said casing constant internal diameter, whereby within said casing the plunger seal portion is tightly engaged with the casing interior While said relief groove forms a Huid passage therewith, said seal portion having a longitudinally extended length less than the length of said blister;

said plunger having further an opening in communication with said cavity, said opening formed in said seal portion and having a length less than said length of said seal portion, said casing interior and said plunger cavity fluidly communicable upon transverse alignment of said opening with said blister, whereby said second component is movable by gravity into said casing interior for mixing with said one component.

No references cited.

ROBERT B. REEVES, Primary Examiner.

F. R. HANDREN, Assistant Examiner. 

12. A SYRINGE COMPRISING IN COMBINATION: AN ELONGATED CASING HAVING AN OPEN REAR END, AND ADAPTED TO CONTAIN WITHIN THE INTERIOR THEREOF ONE COMPONENT OF A CHARGE TO BE INJECTED BY THE SYRINGE, SAID CASING INTERIOR HAVING AT LEAST A PORTION THEREOF A CONSTANT INTERNAL DIAMETER; A BLISTER FORMED IN SAID CASING BY A PORTION OF SAID CASING HAVING A RADIUS GREATER THAN THE NOMRAL RADIUS OF SAID CONSTANT DIAMETER INTERIOR, SAID BLISTER HAVING A CERTAIN LENGTH PARALLEL TO THE LONGITUDINAL AXIS OF SAID CASING; AND AN ELONGATED PLUNGER INSERTABLE INTO SAID CASING REAR END, SAID PLUNGER CLOSED AT A FRONT END, RELEASABLY SEALED AT A REAR END, AND HAVING A CAVITY FORMED THEREIN ADAPTED TO CONTAIN A SECOND COMPONENT OF THE CHARGE TO BE EJECTED BY THE SYRINGE; SAID PLUNGER EXTERIOR HAVING AN ANNULAR SEAL PORTION ADJACENT SAID FRONT END, WITH THE REMAINDER OF THE EXTERIOR OF SAID PLUNGER HAVING AT LEAST ONE RELIEF GROOVE FORMED THEREIN EXTENDED FROM THE SEAL PORTION TO THE REAR END THEREOF, THE OUTER DIAMETER OF SAID SEAL PORTION BEING SUBSTANTIALLY EQUAL TO SAID CASING CONSTANT INTERNAL DIAMETER, WHEREBY WITHIN SAID CASING THE PLUNGER SEAL PORTION IS TIGHTLY ENGAGED WITH THE CASING INTERIOR WHILE SAID RELIEF GROOVE FORMS A FLUID PASSAGE THEREWITH, SAID SEAL PORTION HAVING A LONGITUDINALLY EXTENDED LENGTH LESS THAN THE LENGTH OF SAID BLISTER; SAID PLUNGER HAVING FURTHER AN OPENING IN COMMUNICATION WITH SAID CAVITY, SAID OPENING FORMED IN SAID SEAL PORTION AND HAVING A LENGTH LESS THAN SAID LENGTH OF SAID SEAL PORTION, SAID CASING INTERIOR AND SAID PLUNGER CAVITY FLUIDLY COMMUNICABLE UPON TRANSVERSE ALIGNMENT OF SAID OPENING WITH SAID BLISTER, WHEREBY SAID SECOND COMPONENT IS MOVABLE BY GRAVITY INTO SAID CASING INTERIOR FOR MIXING WITH SAID ONE COMPONENT. 